The present invention relates to an access control system. More particularly, the present invention relates to an access control system that typically connects a plurality of remote locking mechanisms to a central access controller.
The need to control access to secured premises has resulted in a long history of access control devices. Traditionally, simple mechanical locks were incorporated to prevent access to the premises by unauthorized users. However, in such simple mechanical locking environments, mechanical keys needed to be provided to every authorized user. If the lock were changed, new keys needed to be provided to each authorized user, resulting in confusion and undue expense. Such mechanical locks were particularly undesirable in the hotel industry wherein a new user might be authorized each day, but wherein prior authorized users should be denied access.
With the advent of less expensive microelectronics, electronic access controllers were developed that could grant access to an authorized user based on the presentation of a credential such as a card key. While the issuance of different card keys was less expensive than the manufacturing of metal keys, such early access control systems still required security professionals to physically adjust authorized codes at each door in a system. In larger installations, this step was both expensive and time-consuming.
In the next development of the access control industry, all locking mechanisms in a system were wired to a central access controller so that the security professional could reprogram each locking mechanism from a central location (e.g., a command and control station). However, wired units tended to be expensive and complex to install in view of the necessity to physically connect each locking mechanism to a remote device by hard wire. Such shortcomings are adequately defined in the Background of the Invention section of Gonzales et al. U.S. Pat. No. 5,936,544 (“the '544 patent”). The '544 patent eliminated the need for hardwiring by coupling wireless communicators to each door module that could communicate with a central access controller. In operation, a user would present a credential to one of the remotely located door modules and the signal associated with that credential would be wirelessly transmitted from the remote location to the central access controller to determine whether the credential represented an authorized user. If an authorized user was indicated, an access control signal granting access would be sent from the central access controller to the remote door module. Conversely, if the user credential was not recognized by the central access controller, an access control signal denying access would be sent from the central access controller to the remote door module
The shortcomings of the '544 patent are numerous. For instance, the requirement for communication between a remote door module and the central access controller in every instance where a credential was presented resulted in significant absorption of power. Moreover, if numerous requests were made simultaneously, users would experience substantial delays in achieving access through the remote door module as the central access controller attends to the multitude of requests. Yet another shortcoming of the wireless security control system of the '544 patent is that, should the central access controller experience a breakdown, access to all door modules would be rendered impossible.
Rodenbeck et al. U.S. Pat. No. 6,720,861 (“the '861 patent”) overcame some of the battery consumption concerns presented in the '544 patent by providing door access grant or deny decisions at the remote locations, as opposed to requiring a centralized decision. However, this de-centralizing of the locking and unlocking of a door module resulted in other shortcomings. For instance, door modules of the '861 patent could only obtain user updates periodically since a wireless signal would not be transmitted for each event that occurs at the door.
The shortcomings of previous wireless access control systems are evident. In the '544 patent, for instance, battery drain is substantial since each door access grant or deny signal requires communication between the remote location and the central access controller. Conversely, in the system of the '861 patent, grant or deny signals are provided directly at the remote locations, thereby delaying updated user control data from reaching the door control modules. A simple example will demonstrate this flaw. If a new employee is retained and is provided a cardkey at 9:30 AM by security personnel, and then, attempts to use that card key to enter a certain restricted area, access will be denied at that remote location if the system is programmed only to provide updated user control data at midnight of each day. The employee will either need to go back to security personnel or wait until the following day to gain authorized access.
It is therefore a primary object of the present invention to provide a new and improved wireless access control system.
It is another object of the present invention to provide a new and improved wireless access control system that will initiate communication between the remote access control system and the central access control system on a demand basis.
It is yet still another object of the present invention to provide a new and improved wireless access control system that can provide updated access control data from the central access controller to the remote access controller in a non-periodic, on demand manner.
It is still another object of the present invention to provide a new and improved wireless control system which conserves battery power.
It is still another object of the present invention to provide a new and improved wireless access control system that will provide communication between the remote access controller and the central access controller by either (i) an invalid access request signal, (ii) a communication command input at a remote programming mode device coupled to the remote access controller, (iii) activation of a transducer coupled to the remote access controller by a transducer stimulator, or (iv) the expiration of a timer coupled to the remote access controller.
Other objects and advantages of the present invention will become apparent from the specification and the drawings.